Apparatus for drying articles formed from plastic masses.



O. EBERHARD.

APPARATUS FOR DRYING ARTICLES FORMED FROM PLASTIC MASSES.

APPLICATION FILED MAY 1, 1913.

Patented Feb. 24, 1914.

WITNESSES INVENTOR lo )lgh OHSYE enbdrd "6, 7 M

ATTORNEYS COLUMBIA PLANOGRAPH co.. WASHINGTON, D. C.

OTTO EBERHARD, OF HEIDENAU, GERMANY.

APPARATUS FOR DRYING ARTICLES FORMED FROM PLASTIC MASSES.

Application filed May 1, 1913.

Specification of Letters Patent.

Patented Feb. 24:, 1914.

Serial No. 764,781.

To all whom it may concern:

Be it known that I, Dr. O'r'ro Ennnnxnn, a subject of the German Emperor, residing at I-Ieidenau, near Dresden, Germany, have invented certain new and useful Improvements in Apparatus for Drying Articles Formed from Plastic Masses, of which the following is a specification.

The drying of objects formed from plastic masses, particularly those containing a large proportion of water, is attended with difficulty because if the drying is not uniform strains may readily arise in the material and produce undesirable modifications of form.

It has been found that a uniform drying only takes place if during the entire course of the drying all the parts of the object to be dried come perfectly uniformly into contact with the source of heat or with the hot air by means of which the drying is effected. None of the drying devices hitherto adopted fulfils this condition completely. In employing vacuum apparatus with hot plates radiation of heat in various directions differs, even when the material is rested or suspended exactly centrally between two plates. In what are called grid driers the air can never be supplied so uniformly that a completely uniform drying takes place, in particular the lower side of the material or object to be dried does not come into contact with the hot air in the same manner as the upper side, the same applies to the ordinary drying apparatus provided with continu ously moving bands. By means of the novel. drying devices all these defects and difliculties are eliminated owing to the fact that during the drying operation the material under treatment is given a uniform displacement which produces a constant modification in the positions of the several parts of the surface of the object relatively to the source of heat and thereby causes this source of heat to act uniformly on all sides. This displacement, which may advantageously be rotary, can be produced by the apparatus itself or by a separate mechanism.

The novel apparatus can be constructed in various ways. Thus, the material to be dried, such as round rods for example may be arranged on plates in a cabinet, these plates being given a continuous shaking movement. Owing to this shaking movement of their supports the rods receive an alternating reciprocating movement about their own axes. The drying is effected by blowing hot air through theapparatus, or the plates themselves are heated and the apparatus used with or without vacuum.

In the case of round rods the rotary movement can also be produced by displacing an endless cloth on which the material to be dried is placed, stops being arranged over this cloth at various places for preventing the material from participating in the advancing movement of the cloth. In this manner the material is given a continuous rotation. The drying itself can also be effected by means of hot air or in mono. For the drying of plates the process can be carried out in such a manner that the plates held in position, by frames for example, are carried continuously by mechanical means between heating members or in a hot air current with or without the employment of vacuum in accordance with the principle set forth above.

Embodiments of the invention are illustrated by way of example in the accompanying drawing.

Figure 1 illustrates a transverse sectional view of a plate drier adapted to be shaken and suitable for drying round rods. Fig. 2 is a longitudinal sectional view thereof. Figs. 3 and t show similar sectional views of a modified form of the drier according to Figs. 1 and 2. Fig. 5 shows a longitudinal section of a drier with rotating belts, suitable for drying round rods. Fig. (3 is an end view of the same.

In Figs. 1 and 2 f is a frame or receptacle with hollow heated plates The frame is rotatable in bearings while above at the point i appropriate gear is provided for imparting a short reciprocating shaking move ment to the frame. Fixed stops or supports 71 are arranged on the plates 9 and these can be formed by arranging suitable grids on the plates g. Between the supports 7:: the round rods (2 to be dried are arranged and upon the movement of the frame roll to and fro inside the space between two stops 7:: and thus experience a uniform alteration in the face most exposed to the drying source.

With the hollow heating plates 9 there are connected on both sides short pipes s, 10, connected with pipes t, 00 common to them. The pipe t is mounted to turn in a stufling box a disposed in the direction of the axis about which the apparatus swings, the supply pipe 0 leading to the other side of said stufiing box. In the direction indicated by the arrows on the drawings hot air may thus be introduced into the hollow plates g at one side of the apparatus and carried off at the other side.

Figs. 3 and et show another way of constructing the drier of the type shown in Figs. 1 and 2. The plates 7* on which the rods 0 to be dried roll to and fro as the apparatus is rocked, are not made hollow in this case, since heating is not efiected by the plates, but by hot air or the like introduced into the apparatus. For this purpose supply connections s for hot air are attached to the apparatus as in Figs. 1 and 2 but between the several plates 1 at different levels, these connections leading to a common pipe mounted to turn in a stufiing box 24 disposed in the direction of the axis about which the apparatus swings; on the other side, said stufling box is connected with the supply pipe U. The hot air is carried off through corresponding short pipes 20 connected with a common outlet pipe 02. The apparatus may also be operated as a vacuum apparatus if a cock 7 be placed in the outlet pipe :0, but in this case (the cock y being closed) suction must be applied at v instead of supplying hot air.

In Figs, 5 and (5 endless rotating belts y) are provided and over these belts stationary stops 9 extend. The round rods 0 are placed upon the belts 19 between the stops g and owing to the friction on the belts moving beneath the stops 9 experience a uniform rotation. l-Iere also any of the methods of drying described above can be employed, or instead of the belts the stops might be displaced or the belts and the stops may be given a relative displacement.

I claim:

1. An apparatus for drying articles made of plastic material, said apparatus comprising a support on which the articles to be dried rest in their entire length, means for of plastic material, said apparatus comprising a support on which the articles to be drled rest in their entire length, means for giving the said support a uniform constant motion in order to expose the articles to be l dried to the drying source uniformly on all sides, and limiting stops for the articles to be dried.

3. An apparatus for drying articlesniade of plastic material, comprising a support on which the articles to be dried rest in their entire length, and stops arranged above said support, the support and said stops being movable one relatively to the other to give the articles to be dried, which rest on the support, a uniform constant rotary movement.

l. An apparatus for drying articles made of plastic material comprising a longitudinally movable support on which the articles to be dried rest in their entire length, and stationary stops arranged above the support which bring about a uniform constant r0- tary movement of the article to be dried resting on the longitudinally movable support.

5. An apparatus for drying articles made of plastic material, comprising a longitudinally movable belt-like support adapted to support the articles to be dried, in their entire length, rollers over which said support is carried and stationary stops arranged above said support which bring about a uniform constant rotary movement of the articles to be dried, resting on the longitudinally movable support.

in testimony whereof I afiix my signature in, presence of two witnesses.

OTTO BEER-HARD, DR. PHIL. lVitnesses:

ARTHUR Gone, CLARE SIMON.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner 01 Patents, Washington, D. G. 

